U.S. patent application Ser. No. 508,588, filed June 28, 1983, and U.S. patent applications Ser. Nos. 514,928 and 514,929 filed July 18, 1983 describe generally the same bone stapling device described in this application which has numerous novel design features which facilitate driving staples into bone portions during surgery. Generally, the bone stapler described in both those applications and in this application are staplers of the type adapted for use with generally U-shaped staplers. The staplers comprise a housing having a passageway extending from an inlet opening to an outlet opening, which passageway is adapted to guide a single staple moved from the inlet to the outlet opening. Means are provided for biasing a stack of staples into the inlet opening, together with a driver having an end portion adapted to engage the central portion of a staple. The driver is mounted on the housing for sliding movement between a load position spaced from the inlet opening to afford movement of one of the staples of the stack into the passageway, along the passageway with the end portion of the driver pushing the staple, and to an eject position at which the driver pushes the staple out the outlet opening. Also manually activatable drive means are provided for rapidly and forcefully propelling the driver along the passageway from its load position to its eject position to move a staple from the inlet opening to the outlet opening and drive the staple into portions of bone adjacent the outlet opening.
The novel features described in the above mentioned prior applications include a removable cartridge which precludes leaving a staple in the stapler that could be inadvertently driven after the cartridge is removed. The case in that cartridge comprises guide wall means defining an inner surface at the end of a stack of staples opposite a follower and side walls projecting normal to the inner surface, which side walls have opposed transverse openings at the inner surface and aligned with the passageway when the cartridge is in the stapler. The inner surface defined by the guide wall means defines a portion of the passageway for the driver at the inlet opening, with the driver being movable through the transverse openings and along the inner surface between its load and the eject positions. Thus because all of the staples remain within the cartridge until they are driven, the user can be assured that all the staples are removed from the stapler when the cartridge is removed.